Known prior art computer networks comprise a plurality of interconnected computer entities. In the prior art, in order to manage prior art computer networks, network management systems have relied on centralisation of information at a management station. A management station can comprise one or more computer entities each provided with a management system allowing a human user to view a screen at which the whole network, or sections of the network are represented graphically as a set of nodes and links, and at which a set of parameters of a plurality of individual computers can be examined at the centralised management station. One or more human operators apply network management policies in order to perform network management operations such as configuring the network, detecting and repairing faults in the network, undertaking network accounting, optimising performance of the network, and enforcing security.
Examples of prior art computer network management systems include the known HP Open View network management system.
Another type of prior art computer network comprises a peer to peer network. In a peer to peer network, a plurality of computer entities communicate with each other on an equal basis. There is no centralised management system and no individual human network managers to apply overall control of policies for configuring the network. The nature of peer to peer networks is that they are scaleable by addition of extra peer computer entities, which when joining the network, communicate with other peer computer entities on an equivalent basis. No single computer entity has the capability to manage or monitor the whole of the peer to peer network.
One problem with prior art peer to peer networks, is that the control which a user has over their computer entity, once it has joined a peer to peer network, is very crude. The user has only a very basic control over which other computer entities can access the user's computer entity and there can arise conflicts in determining which user can access the computer entities at any one time in known peer to peer networks.
Other problems which occur in prior art peer to peer computer networks are those of users being incentivised to join a network. In particular, by joining a network the owner of a computer entity may find that their computer is being used heavily by other users, and yet those other users provide few resources in return. Computer entities which routinely use services in a peer to peer network, but rarely provide a resource are known as ‘free loaders’ or ‘free riders’. For example, in a Napster® network, a user may routinely download music files onto their own computer, but never supply any music files on their own computer for access by other users.
It is a fundamental assumption in a peer to peer network, that each computer entity will be able to give resources to the network, as well as receive resources from the network. Any free loaders in the network therefore need to be isolated, and excluded from the network. However, in a prior art peer to peer network, since all computers are treated as equivalent by the peer to peer protocol, and there is no overall one person or computer in charge of network management, there is no mechanism for isolation of a free loader computer in a network.